Gate-valve



(No Model.)

H. N. LIBBEY.

GATE VALVE.

No. 579,114. Patented Mar. 16, 1897. E53. v is f f IHIII G 4 J C Ki i r *2 EH2. 1

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llnrrnn Starts PATENT HENRY N. LIBBEY, OF BOSTON, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO CHARLES P. PERKINS, OF DANVERS, MASSACHUSETTS.

GATE-VALVE.

SPECIFICATION forming part of Letters Patent No. 579,114, dated March 16, 1897.

Application filed March 2,1896. Serial No. 581,611. (No model.)

T0 (tZZ whom it puny concern:

Beit known that I, HENRY N. LIBBEY, a citizen of the United States, and a resident of Boston, in the county of Suffolk and State of Massachusetts, have invented new and useful Improvements in Gate-Valves, of which the following, taken in connection with the accompanying drawings, is a specification.

This invention relates to improvements in gate-valves for steam and liquids; and it has for its object to permit the steam or liquid in the outlet end to escape freely when the valve is closed, which is very desirable in case of repairs to the pipes beyond the valve or for the purpose of preventing the liquid in the pipe from freezing in cold weather, as will hereinafter be more fully shown and described, reference being had to the accompanying drawings, wherein- Figure 1 represents an end view of the improved valve, showing the gates closed. Fig. 2 represents a vertical section on the line 2 2 in Fig. 1, showing the gates closed. Fig. 3 represents a similar vertical section showing the gates open. Fig. 4 represents a detail side view of the gate-plug and its gates, and Fig. 5 represents an end view of said plug and gates.

Similar letters refer to similar parts wherever they occur on the different parts of the drawings.

In the drawings, A represents the valveshell, having supply-branch B and deliverybranch 0, as shown.

B and O are perforated valve or gate seats at the inner ends of the respective branches B and O. Below the said branches B O the valve-shell is extended as a chamber A, to which is detachably secured the screwthreaded perforated cap or cover D, as shown.

Centrally within the valve-shell is located the longitudinally-adjustable gate-plug E, havingatransverse perforation E,coincidin g, or nearly so, with the perforations Z) c in the valve-seats B 0 when the valve is open, as fully shown in Fig. 3.

The plug E is guided in a suitable manner Within the shell A and is operated up and down within said shell by means of a screwthreaded valve-spindle F, journaled in the upper end of the shell A and provided at its upper end with a suitable hand-wheel f, as is common in devices of this kind.

G represents the gland, and H the stuffingbox, for the valve-spindle, as usual.

Below the plug-perforation E are pivoted at '1: it the valves I K, adapted to close against the respective valve-seats B O, as represented in Fig. 2.

7c is a perforation in the valve K for the purpose of letting out the water from the branch O and pipes connected thereto when the valve is closed, as shown in Fig. 2.

In the bottom of the cap D is an exhaust port or opening d, adapted to be closed by a valve 6, attached to or forming a part of the lower end of the plug E when the valves I and K are open, as shown in Fig. 3.

The operation is as follows: The valves I K are opened when the plug E is moved clownward, as shown in Fig. 3, when communication is established between the branches B and O, and during such position of the said valves the vent cl is closed by the valve e, as shown in said Fig. WVhen the plug E is raised upward and the valves I K closed against their seats B O,the exhaust-port at is open in communication with the branch 0 by means of the perforation 7c in the valve K, thus permitting the liquid or back pressure in the branch 0 and pipes connected thereto to escape through the port or opening cl, for the purpose hereinabove set forth.

'IIaving thus fully described the nature, construction, and operation of my invention, I wish to secure by Letters Patent and claim- In a gate-valve having supply and delivery branches, and valve-seats thereon, combined With a perforated adjust-able plug, valves or gates pivoted to the latter, one of said valves having a port or perforation, a valve on the lower end of the plug and an exhaust-port in the lower end of the valve-case adapted to be closed by the plug when the gate-valve is open and to serve as a relief-vent when the valve is closed substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing Witnesses, on this 8th day of February, A. D. 1890.

HENRY N. LIBBEY.

\Vitnesses:

ALBAN ANDREN, HENRY R. PAGE. 

